The present invention is directed to an apparatus for the direct optical reception of a plurality wavelengths incoming on a common channel and being distributed into a plurality of separate channels leading to different opto-electronic detectors.
In the wavelength region around 1.3 .mu.m and 1.6 .mu.m, an optical fibers offer broad optical windows, particularly compared to the bandwidth used by the electrical modulation. There are therefore a number of system proposals to utilize the windows with a plurality of modulated wavelengths. The desired wavelength is then selected at the receiver by a hetrerodyne reception or by direct reception with filters. Heterodyne reception, in fact, offers the best properties for the transmission. Its outlay, however, is extremely high due to the tuneable, extremely narrow-banded, local oscillators and due to the measures to prevent fluctuations in the polarization of the transmitted waves.
The above-mentioned direct reception offers costbeneficial solutions for data rates up to the region of 10 Gbits/seconds as required, for example, for video or, respectively, the HDV (high definition video) or HDTV (high definition television video) distribution. It is known to construct such direct receivers of discrete components or in modules. The optical waves are conducted between the individual function elements as free beams. However, the costs of the solutions are prohibitively high for the intended, broad employment